Cancer Genetics Pre-Test
Before your DNA is tested for markers of higher cancer risk, you and your doctor will review several key pieces of information. This ensures that you are fully informed throughout the process, determines whether genetic cancer testing is necessary or recommended for you, and allows for the most accurate results and best possible medical care.
Personal and Family Medical History
The first step of any genetic cancer testing is gathering the patient’s personal and family medical history. Be prepared to answer your doctor’s questions regarding your own health and your family history of cancer to the best of your ability. Your doctor will want to know about whether you have ever received a cancer diagnosis and whether close family members on the same side of your family (such as your parents and grandparents) have had the same types of cancer. This helps to determine risk before your genetic testing takes place.
Possible Test Results
Before testing your DNA, your doctor or a genetic counselor will explain the three possible outcomes of your genetic test. They are:
- Positive, meaning that a pathogenic or likely pathogenic variant associated with an increased risk of developing cancer was found. This means that you and your family are at an increased risk for cancer, and your doctor will likely wish to move forward with a plan to manage this risk.
- Negative, meaning that no pathogenic or likely pathogenic variants were found. This means that you do not carry any of the hereditary cancer pathogenic variants that were included on the test. When interpreted in the context of your personal and family history, it might mean one of several things. It can be a “true-negative”, that you did not inherit your family’s cancer risk and that you are not at a higher risk for the types of cancer that were tested for. In some cases, due to a significant family history of cancer, you and your family might still be at increased risk for a hereditary cancer predisposition. This risk might be due to genetic factors that have not yet been discovered or that where not detectable by the test. In either scenario, I you would still be encouraged to prioritize a healthy lifestyle and adhere to routine cancer screening guidelines in order to maintain your health.
- Inconclusive, meaning that your tested genes have some alteration, but it can’t be determined whether this puts you at an increased risk for developing cancer. Typically, a doctor will not make specific recommendations based on an inconclusive test result alone. However, you should continue to follow healthy lifestyle habits and adhere to recommended cancer screening guidelines for the general population to minimize your cancer risk as you would given a negative result.
Genetic Testing Limitations
Patients should understand that genetic testing has some limitations. These include the fact that tests are incapable of testing every gene or genetic variant associated with an increased risk for cancer. This means that while your genetic cancer testing may have yielded a negative result, it is still possible to be at an increased risk for types of cancer that were not tested for. Your doctor will review the limitations of your testing and answer any questions you may have.
Some states prevent discrimination by employers or health insurance companies based on genetic test results. The US Genetic Information Nondiscrimination Act (GINA) also prohibits this type of discrimination in many contexts. However, this does not protect against discrimination from the military or life, disability, or long-term care insurance. As such, some patients choose to wait until they have obtained a life insurance policy before undergoing genetic testing. To learn more, visit ginahelp.org.
Genetic counseling is an important part of the cancer genetic testing process. Depending on your situation, your doctor may recommend genetic counseling both before and after you receive your test results. A genetic counselor is a medical professional who has extensive knowledge of genetics and is trained to explain the subject, answer questions, and guide a patient regarding their medical care.
Schedule an Appointment
To get started with cancer genetic testing, schedule an appointment with Carnegie Women’s Health. Call our New York, NY office at (315) 628-7063 or request an appointment online.
Frequently Asked Questions
Do I have a higher risk of getting cancer?
If you have a family history of cancer, you may be at an increased risk. This is true for patients who have multiple relatives on the same side of their family with the same type of cancer, a parent, sibling, or child who was diagnosed with cancer before age 50, a male relative with breast cancer, or those with Eastern European or Ashkenazi Jewish ancestry.
Why is cancer becoming more common?
The primary reason behind cancer becoming more common is the increasing average lifespan.
Should I have genetic testing for cancer?
Your doctor may recommend genetic testing for a higher risk of cancer if you fall into a higher risk category. Genetic testing helps determine if you carry a genetic mutation that would put you at an increased risk for cancer.
How is genetic cancer testing done?
A genetic cancer test works by taking a sample of your blood, hair, saliva, cheek cells, or other tissue which can be analyzed in a lab. There, scientists will check for genetic mutations that indicate a higher risk for cancer.
How long does genetic testing take for cancer?
It typically takes about two to four weeks before results from a genetic cancer test can be reported to patients.